1. Field of the Invention
This invention relates to a method of detecting and quantitatively determining selenium and a monitor therefor, and more particularly, it is concerned with a method of detecting quantitatively determining gaseous selenium at temperatures lower than that in the atomic absorption spectroscopic analysis of the prior art, and a monitor apparatus therefor.
2. Description of the Prior Art
High sensitivity detection and quantitative determination of selenium is now being required as a result of the development of various compounds containing selenium in various fields of the industry, for example, in the production of semiconductors, alloys, ceramics and glass. For this requirement, the atomic absorption spectroscopic analysis method has hitherto been carried out comprising atomizing selenium at high temperatures, e.g. 2000.degree. C. or higher and then detecting the atomic absorption spectrum characteristic of selenium. The atomic absorption spectrum of selenium has a sharp peak at a wavelength of 196.03 nm, as shown in FIG. 5 (quoted from Catalogue of Hamamatsu Photonics KK). The general structure of an apparatus for the atomic absorption spectroscopic analysis utilizing this peak according to the prior art is as shown in FIG. 6 in which a light from light source 1 is caused to enter and pass through part 2 of of an atomized sampl, then to pass through photoselective means 3, such as a monochromator, and finally to enter photometric means 4-6 comprising a detector 4, and amplifier 5 and a metering part 6, where the light is detected and determined quantitatively. In part 2 relating to an ized sample, an atomizing temperature of 2000.degree. C. or higher is required for atomizing selenium and to this end, a flame is generally used as a convenient method.
However, the above described method of detecting selenium by utilizing an atomic absorption spectrum requires such a high temperature (atomizing temperature) that it is not suitable for detecting selenium at a temperature below the atomizing temperature. That is, for gaseous SeX at a temperature lower than the atomizing temperature, there is no method for detecting and quantitatively determining it, nor is there a monitor for detecting and quantitatively determining it, in situ.